Generally, mcmc_IMIFA() is used for running the model and creating a raw results object, on which get_IMIFA_results() is then called to prepare these results for posterior inference. The output of the second call be visualised in many ways using plot.Results_IMIFA().

For a more thorough intro, the vignette document is available as follows:

vignette("IMIFA", package="IMIFA")

However, if the package is installed from GitHub the vignette is not automatically created. It can be accessed when installing from GitHub with the code: